// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/json/string_escape.h"

#include <stddef.h>

#include "base/macros.h"
#include "base/strings/string_util.h"
#include "base/strings/utf_string_conversions.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace base {

TEST(JSONStringEscapeTest, EscapeUTF8)
{
    const struct {
        const char* to_escape;
        const char* escaped;
    } cases[] = {
        { "\b\001aZ\"\\wee", "\\b\\u0001aZ\\\"\\\\wee" },
        { "a\b\f\n\r\t\v\1\\.\"z",
            "a\\b\\f\\n\\r\\t\\u000B\\u0001\\\\.\\\"z" },
        { "b\x0f\x7f\xf0\xff!", // \xf0\xff is not a valid UTF-8 unit.
            "b\\u000F\x7F\xEF\xBF\xBD\xEF\xBF\xBD!" },
        { "c<>d", "c\\u003C>d" },
        { "Hello\xe2\x80\xa8world", "Hello\\u2028world" },
        { "\xe2\x80\xa9purple", "\\u2029purple" },
    };

    for (size_t i = 0; i < arraysize(cases); ++i) {
        const char* in_ptr = cases[i].to_escape;
        std::string in_str = in_ptr;

        std::string out;
        EscapeJSONString(in_ptr, false, &out);
        EXPECT_EQ(std::string(cases[i].escaped), out);
        EXPECT_TRUE(IsStringUTF8(out));

        out.erase();
        bool convert_ok = EscapeJSONString(in_str, false, &out);
        EXPECT_EQ(std::string(cases[i].escaped), out);
        EXPECT_TRUE(IsStringUTF8(out));

        if (convert_ok) {
            std::string fooout = GetQuotedJSONString(in_str);
            EXPECT_EQ("\"" + std::string(cases[i].escaped) + "\"", fooout);
            EXPECT_TRUE(IsStringUTF8(out));
        }
    }

    std::string in = cases[0].to_escape;
    std::string out;
    EscapeJSONString(in, false, &out);
    EXPECT_TRUE(IsStringUTF8(out));

    // test quoting
    std::string out_quoted;
    EscapeJSONString(in, true, &out_quoted);
    EXPECT_EQ(out.length() + 2, out_quoted.length());
    EXPECT_EQ(out_quoted.find(out), 1U);
    EXPECT_TRUE(IsStringUTF8(out_quoted));

    // now try with a NULL in the string
    std::string null_prepend = "test";
    null_prepend.push_back(0);
    in = null_prepend + in;
    std::string expected = "test\\u0000";
    expected += cases[0].escaped;
    out.clear();
    EscapeJSONString(in, false, &out);
    EXPECT_EQ(expected, out);
    EXPECT_TRUE(IsStringUTF8(out));
}

TEST(JSONStringEscapeTest, EscapeUTF16)
{
    const struct {
        const wchar_t* to_escape;
        const char* escaped;
    } cases[] = {
        { L"b\uffb1\u00ff", "b\xEF\xBE\xB1\xC3\xBF" },
        { L"\b\001aZ\"\\wee", "\\b\\u0001aZ\\\"\\\\wee" },
        { L"a\b\f\n\r\t\v\1\\.\"z",
            "a\\b\\f\\n\\r\\t\\u000B\\u0001\\\\.\\\"z" },
        { L"b\x0f\x7f\xf0\xff!", "b\\u000F\x7F\xC3\xB0\xC3\xBF!" },
        { L"c<>d", "c\\u003C>d" },
        { L"Hello\u2028world", "Hello\\u2028world" },
        { L"\u2029purple", "\\u2029purple" },
    };

    for (size_t i = 0; i < arraysize(cases); ++i) {
        string16 in = WideToUTF16(cases[i].to_escape);

        std::string out;
        EscapeJSONString(in, false, &out);
        EXPECT_EQ(std::string(cases[i].escaped), out);
        EXPECT_TRUE(IsStringUTF8(out));

        out = GetQuotedJSONString(in);
        EXPECT_EQ("\"" + std::string(cases[i].escaped) + "\"", out);
        EXPECT_TRUE(IsStringUTF8(out));
    }

    string16 in = WideToUTF16(cases[0].to_escape);
    std::string out;
    EscapeJSONString(in, false, &out);
    EXPECT_TRUE(IsStringUTF8(out));

    // test quoting
    std::string out_quoted;
    EscapeJSONString(in, true, &out_quoted);
    EXPECT_EQ(out.length() + 2, out_quoted.length());
    EXPECT_EQ(out_quoted.find(out), 1U);
    EXPECT_TRUE(IsStringUTF8(out));

    // now try with a NULL in the string
    string16 null_prepend = WideToUTF16(L"test");
    null_prepend.push_back(0);
    in = null_prepend + in;
    std::string expected = "test\\u0000";
    expected += cases[0].escaped;
    out.clear();
    EscapeJSONString(in, false, &out);
    EXPECT_EQ(expected, out);
    EXPECT_TRUE(IsStringUTF8(out));
}

TEST(JSONStringEscapeTest, EscapeUTF16OutsideBMP)
{
    {
        // {a, U+10300, !}, SMP.
        string16 test;
        test.push_back('a');
        test.push_back(0xD800);
        test.push_back(0xDF00);
        test.push_back('!');
        std::string actual;
        EXPECT_TRUE(EscapeJSONString(test, false, &actual));
        EXPECT_EQ("a\xF0\x90\x8C\x80!", actual);
    }
    {
        // {U+20021, U+2002B}, SIP.
        string16 test;
        test.push_back(0xD840);
        test.push_back(0xDC21);
        test.push_back(0xD840);
        test.push_back(0xDC2B);
        std::string actual;
        EXPECT_TRUE(EscapeJSONString(test, false, &actual));
        EXPECT_EQ("\xF0\xA0\x80\xA1\xF0\xA0\x80\xAB", actual);
    }
    {
        // {?, U+D800, @}, lone surrogate.
        string16 test;
        test.push_back('?');
        test.push_back(0xD800);
        test.push_back('@');
        std::string actual;
        EXPECT_FALSE(EscapeJSONString(test, false, &actual));
        EXPECT_EQ("?\xEF\xBF\xBD@", actual);
    }
}

TEST(JSONStringEscapeTest, EscapeBytes)
{
    const struct {
        const char* to_escape;
        const char* escaped;
    } cases[] = {
        { "b\x0f\x7f\xf0\xff!", "b\\u000F\\u007F\\u00F0\\u00FF!" },
        { "\xe5\xc4\x4f\x05\xb6\xfd", "\\u00E5\\u00C4O\\u0005\\u00B6\\u00FD" },
    };

    for (size_t i = 0; i < arraysize(cases); ++i) {
        std::string in = std::string(cases[i].to_escape);
        EXPECT_FALSE(IsStringUTF8(in));

        EXPECT_EQ(std::string(cases[i].escaped),
            EscapeBytesAsInvalidJSONString(in, false));
        EXPECT_EQ("\"" + std::string(cases[i].escaped) + "\"",
            EscapeBytesAsInvalidJSONString(in, true));
    }

    const char kEmbedNull[] = { '\xab', '\x39', '\0', '\x9f', '\xab' };
    std::string in(kEmbedNull, arraysize(kEmbedNull));
    EXPECT_FALSE(IsStringUTF8(in));
    EXPECT_EQ(std::string("\\u00AB9\\u0000\\u009F\\u00AB"),
        EscapeBytesAsInvalidJSONString(in, false));
}

} // namespace base
